cnam / react-from-json

Declare your React component tree in JSON

react-from-json

Declare your React component tree in JSON

Example

Intro

react-from-json lets you render React

<Burger chain="Wahlburger">
  <Patty variant="impossible" />
</Burger>

from JSON

{
  "type": "Burger",
  "props": {
    "chain": "Wahlburger",
    "children": {
      "type": "Patty",
      "props": {
        "variant": "impossible"
      }
    }
  }
}

It also supports non-recursive structures.

Install

npm install --save react-from-json

Usage

import React from "react";
import ReactFromJSON from "react-from-json";

const entry = {
  type: "Burger",
  props: {
    chain: "Wahlburger",
    children: {
      type: "Patty",
      props: {
        variant: "Impossible"
      }
    }
  }
};

const mapping = {
  Burger: ({ chain, children }) => (
    <div>
      <h1>{chain}</h1>
      <div>{children}</div>
    </div>
  ),
  Patty: ({ variant }) => <span>{variant}</span>
};

const Example = () => {
  return <ReactFromJSON entry={entry} mapping={mapping} />;
};

Flat trees

react-from-json also supports flat, non-recursive structures via the special <ComponentLookup /> component. This is useful when working with typed systems like GraphQL, and you need to avoid unions.

The <ComponentLookup /> component

<ComponentLookup /> simply maps to another component defined in a components object. If you were using it in React, you would use it like:

<ComponentLookup componentType="Button" componentIndex={0} />

which would look up the Button component at index 0 in the components object, resolving to:

<Button id={0}>Hello, World!</Button>

For react-from-json we use JSON, so we would write this:

{
  "type": "ComponentLookup",
  "props": {
    "componentType": "Button",
    "componentIndex": 0
  }
}

The id here is set by the componentIndex, since we didn't specify one in the JSON. See this comment on IDs for more information.

Example

Here's the same example as above, instead using a <ComponentLookup /> for entry.props.patty, and providing a separate components object.

import React from "react";
import ReactFromJSON from "react-from-json";

const entry = {
  type: "Burger",
  props: {
    chain: "Wahlburger",
    patty: {
      type: "ComponentLookup",
      props: {
        componentIndex: 0,
        componentType: "Patty"
      }
    }
  }
};

const mapping = {
  Burger: ({ chain, patty }) => (
    <div>
      <h1>{chain}</h1>
      <div>{patty}</div>
    </div>
  ),
  Patty: ({ variant }) => <span>{variant}</span>
};

const components = {
  Patty: [
    {
      type: "Patty",
      props: {
        variant: "Impossible"
      }
    }
  ]
};

const Example = () => {
  return (
    <ReactFromJSON entry={entry} mapping={mapping} components={components} />
  );
};

A note on ids

react-from-json will map id from the root of your component JSON to the React component's id prop. Likewise, if you specify id under props, it will use this. If you use the <ComponentLookup /> component, react-from-json will use the array index as id unless another id is specified. Your id will always take priority.

With TypeScript

react-from-json supports generic types for use with TypeScript.

import { entry, mapping, components } from "./aboveExample";
import ReactFromJSON from "react-from-json";

interface Components {
  Patty: object[];
}

interface Mapping {
  Burger: React.ReactNode;
  Patty: React.ReactNode;
}

class BurgerReactFromJSON extends ReactFromJSON<Mapping, Components> {
  render(): JSX.Element {
    return super.render();
  }
}

const Example = () => {
  return (
    <BurgerReactFromJSON
      entry={entry}
      mapping={mapping}
      components={components}
    />
  );
};

License

MIT © hydrateio